You should get a valid mpatrol.log. To find out what a valid log is check out the mpatrol documentation http://mpatrol.sourceforge.net/doc/files/mpatrol.pdf[10]
I recommend compiling some more test programs. Instead of environment variables in Windows you can use the export command. Type this before executing the test program

$ export MPATROL_OPTIONS="LOGALL"

To use multiple different options simply divide them by a space character